A long black cardi; long enough to cover the bum and any post-birth stains, and also something I could then use on a lazy day at home with baby and not looking quite like I haven't bothered getting dressed! Plus it's cheap enough to not worry too much about keeping it nice.

This was one thing missing from my hospital bag last time when I got caught ahort at 36 weeks! I went for a men's one in the end. Plain, black, jersey material from Amazon. It's perfect and only £9.99.